When the download folder does not exist, change the download folder to a user's "Downloads"

chrome/browser/ui/download/download_tab_helper.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/download/download_tab_helper.h"
 
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/download/download_manager.h"
 #include "chrome/browser/download/download_request_limiter.h"
 #include "chrome/browser/download/download_util.h"
@@ skipping 36 matching lines @@
   // another thread.
   save_package_ = new SavePackage(tab_contents_wrapper_);
   save_package_->GetSaveInfo();
 }
 
 void DownloadTabHelper::OnSaveURL(const GURL& url) {
   DownloadManager* dlm = tab_contents()->profile()->GetDownloadManager();
   dlm->DownloadUrl(url, tab_contents()->GetURL(), "", tab_contents());
 }
 
-// Used in automated testing to bypass prompting the user for file names.
-// Instead, the names and paths are hard coded rather than running them through
-// file name sanitation and extension / mime checking.
 bool DownloadTabHelper::SavePage(const FilePath& main_file,
                                  const FilePath& dir_path,
                                  SavePackage::SavePackageType save_type) {
   // Stop the page from navigating.
   tab_contents()->Stop();
 
   save_package_ =
       new SavePackage(tab_contents_wrapper_, save_type, main_file, dir_path);
+  // Skips GetSaveInfo() and directly calls Init().
+  // We do not have to explicitly disable the select file dialog
+  // since we skip the process that can show the dialog.
   return save_package_->Init();
 }
 
+string16 DownloadTabHelper::SavePageBasedOnDefaultPrefs() {
+  tab_contents()->Stop();
+
+  save_package_ = new SavePackage(tab_contents_wrapper_);
+  // Disables the select file dialog.
+  save_package_->SetShouldPromptUser(false);
+  // This GetSaveInfo() calls save_package_->Init() in the background.
+  save_package_->GetSaveInfo();
+  return tab_contents()->GetTitle();
+}
+
 bool DownloadTabHelper::CanDownload(int request_id) {
   if (delegate_)
     return delegate_->CanDownload(request_id);
   return true;
 }
 
 void DownloadTabHelper::OnStartDownload(DownloadItem* download) {
   DCHECK(download);
 
   BlockedContentTabHelperDelegate* blocked_content_delegate =
@@ skipping 21 matching lines @@
 
   return handled;
 }
 
 void DownloadTabHelper::DidGetUserGesture() {
   DownloadRequestLimiter* limiter =
       g_browser_process->download_request_limiter();
   if (limiter)
     limiter->OnUserGesture(tab_contents());
 }